Solo-playing automatic piano.



M. CLARK.

soLo PLAYING AUTOMATIC PIANO.

vAPPLIGAI'ION ILED MAY 17, 19,11. n

Patented A131230, 1912.

M. CLARK.

soLo PLAYING AUTOMATIC PIANO.

lA'PILIOAIION FILED MAY 17. 1911.

Patented Apr. 30, 1912.

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o o H It is cunionvpln .'[b all whom il upm. um rw of a n m ke notes Referring lcnhzffl ai', C. f h s 1'@ in.: show I), :xx-rang@ asuma. whloh the wspmftwe wmumzb'rd -t'oration ot the contr pneumatic, D.

duct et the tracker board. The duct, L2, is also provided with a second aperture, L, through which under certain conditions it may communicate with the outer air, that is, -through which atmospheric pressure may be admitted to the duct. When a per- I oller sheet registers I ot one of the ducts, FX, atmospheric pressure is admitted through the tube, LX, to the interior ot the pneumatic, L5; since this pneumatic is contained in a chamber which is under a pressure lower than atmospheric, I

the result is that the pneumatic, L5, is eX- l seated over the aperture, L5, serving to keep it closed to permit proper operation of the motor pneumatic when such operation is initiated through the high tension action, H. In case the low vacuum action is brought intoservice, the valve, L2, is carried with the valve, L4, and seated over the aperture, HG, while tlte valve, L, closesthe aperture, L, thus completely excluding atmospheric pressure from the passages, L2 and H2, and insuring actuation ot' the motor pneumatic, D. .t

Duc to the ditterence in the two partial vacuums in the chambers, L1 and H1, respectively, there arises another difficulty in consequence of the fact that both ducts, L2 and H2, connect with a common duct., D2. then a primary pneumatic of the action, H, is in service, having opened its valve, ll, the higher vacuum will be operative through the duct, H2, as well as through the duct, L2, unless there is some provision for preventing it. ln that case, the pressure on the valve, L1, w iuld be greater on the side facing the chamber, L1, than on the side which stands in the duct, L2, so that the greater pressui'e from within would vtend tounsea tl the Valve, L4, and relieve the 'higher vacuum ot the chamber, H1, rendering it no more effec` tire for actuating the motor pneumatic than 'the lower vacuum ofthe chamber, L1, would ,I tion; as indicated in Fig. l, this valve is I with the mouth, F1, of the tracker board,

panded and u'nseats the valve, Lt, from thc apertme,L2, moving it to a position covering the aperturepL. rlhe exhaust of the eham ber, L1, is thus admit-ted to the duct, L1, and thence into the corresponding motor pneumatic, D, with which it communicates. This rarecation ot' the air within the bellows, L5, which is exteriorly subject to atmospheric pressure, causes it to collapse and to actuate its 'key striker, D1, thus sounding the desired note.

As thus tar described, the construction and modeof operation a re that of a usual and well known type ot' pneumatic player action. The above description applies equally well tothe arrangement of the high tension action, H, and its connections which are shown in Fig. l, with reference. numerals corresponding to those of the low tension action, he. ,To prevent this undesied result, there L. The tubes, HX, are shown leading to is placed in the passage, L2, near itsl junccertain ducts oit the tracker hoard, F. Fig. 3 indicating that the end portions ot the tracker board in this case are taken up with the ducts corresponding to this high vacuum action, while the middle part is connected with the primary pneumatics of the low tension action, L.

By reference to Fig. 1, it may be noted that both of therducts, L2 and H2, connect with a single duct. D2, leading to the motor Vith no more parts than have already been dcscribefh'it will loc seen that both ot the ducts, L2 and H2, would normally be open to the atmosphere through their respective apertures, L6 and H, and that though the operation of primary, L2, for example, vvoulhnnwe-tlie valve, L4, to close the aperture, L, the aperture,` HG, would still remain open and the partial vacuum of the chamber, L1, would be relievcd thcrctln'oiigh, instead of operating the motor pneumatic, D, as intended. Troper operation on the high vacuum side would be similarly defeated through the aperture, L, which would normally remain open in spite ot the closing-of the aperture, H1". rllo overcome this ditliculty, there is provided what 'may bctermed a floating valve, L1, carried between springs, L8, on an extended portion of the pitman, L9, which carries the valve, Lf, in normal positign -with the duct, D2, a flap valve, L10. Since the pressure in the passage, L2, would always be greater than that resulting from the partial vacuum' of the chamber, H1, and the latter when communicated through the duct, D2, will operate to cause the valve, L1, to seat, and thus .automatically cut ott communication with the low vacuum action and its passages. In connection with this last described valve, L10, it. may be noted that it incidentally accomplishes also the function of the supplemental valve, U, as *far as it relates to the aperture, L, since it effectively cuts oft' all connection of this aperture with the duct, H2, when the .latter is in service. This observation suggests a modified form of supplemental valve to replace the valve, L", andv such. modification is illustrated in Fig. 4. It consists of a supplemental primary pneumatic, L11, mounted exteriorly on the chamber, L1, to communicate therewith through a port, L12, so as to be normally collapsed underthe 'nfluence of the partial vacuum in the chamber, L1. A duct, L13, branching from the duct which leads into the primary pneumatic, L", furnishes atmos pheric pressure from the cracker board to the pneumatic, L11, whenever such pressure is similarly furnished lto -the pneumatic, L", so that the two will be simultaneously exp'anded, The movable Wall of the pneutively ciiinieeted with each otsaiiil valv s by the simultaneous expansion ot the primaries, L5 and L, the valves, L* and L70, are properly seated over the apertures, -LG and HG, respectively, and thus the partial vacuum ofthe chamber, L1, vis communicated to the motor pneumatic through the ducts, and D2, without danger of being relieved.

It will he understood that the perforated note sheet, which is intended to control the operation ofthis action, will have perforations cut throughout the middle )ortion of its length corresponifling to the notes ci. the accompaniment, so as to register with the ducts,F1,-while the pertoiations corresponding to the notes of the melody will be disposed in the marginal portions oit the sheet, so as to register with the ducts, Fh. In the case ol music of the class which may be termed purely instrui'mzntal7 and in which :5 it is' not 'particularly desired to accentuate the theme, the perforations would be confined to the middle portion ol the sheet, so as to register only with the ducts, F1, the duets, Fh, remaining covered by the unperforated margins ol the sheet, so that the high vacuum or melody action would. not be brought into service.

l claim l. ln an automatic musical instrument, in.

conibination'with a key striker and a motor pneumatic operatively connected therewith, a duct leading :trein said motor pneumatic and havii'ig two branches, each branch he- \ing provided with two apertures, one ot' A10 said apertures in each branch being posi-- tioned to ceiniiiunicate with the atmosphere at normalprossime, the other apertures comn'iiinicating with separate sources of air at ditlferent pres ires. respectively, other than normal' pressure, a valve in each branch adapted for closingalternately the two apertures thereof, a primary pneumatic operaf i e i a supplemental valve ae: :iteil tor closing the noifnial pressure aperture oi' one oi the hrancli'ducts, i'iieans tor moving said valve siinullaneously with 4(he valve ot the other bfancli i'luct, a tracker l' oaril provided with a duct coiiresijioiiding u each of the primary p 'ieun'iatics1 and ii'ieaiisy miniieetiiig the lattei.l withtl'ieir respective duets.

2. ln an autoii'iatic musical ii'istriiii'ient, in

combination with a key striker and a motor pneumatic operatively connected therewith, a duct leading from said motor pneumatic and having two branches, each branch being provided with two apertures, one of said apertures in each branch being positioned to admit atmosphere at normal pressure, the other apertures connecting', one with a low vacuum and the other with a source of higher vacuum, a valve for each branch adapted -tor closing alternately the two apertures thereof, a primary pneumatic operatively connected with each of said valves, a supplemental valve adapted for closing the normal pressure aperture of one of the branch ducts; meansitor moving said valve simultaneously with the valve of the other branch duct, a check valve in the ducteomniunicating with the low vacuiun, a 'tracker board provided with a duct correspending to each of the primary -pneumatics, and means connecting the latter with their respective ducts.

3. ln an automatic musical instrument, in combination with a key striker and a motor '[nieumatic operatively connected therewith, a duct leading from said motor pneumatic and having two branches, each branch being provided with two apertures, one of said apertures 'in each branch being positioncd to admit atn'iosphere at lnorn'ial pressure, the other apertures connecting, one with a low vacuum and the other with a higher vacuum, a valve for each branch adaptedfor closing alternately the two apertures thereof, a primary pneumatic operatively connected with each of said valves, a supplementall primary pneumatic,

a leal( port connecting the same with one otsaid vacuums, a duct connecting the supplemental vprimary with the primary which operates the valve controlling said vacuum, a valve carried by the movable wall of the supi'ileinental primary, in position tor closing the normal pressure aperture of the duct which connects with the other vacuum, a tracker board provided with a duct corresponding toeaoli of the lirst two prin'iary pneiiiniatics,and means coniiectii'ig the latter with their resiiective ducts..

.ln testimony whereot l have hereunto set my hand at Chicago, .lllinois, this 15th day ot May, 1x91 l.

MEIJV'ILLE CLARK. Vi" i lnesses Lucy l. S'ionn, EDN n M. hilAelN'rosni. 

